http://www.delete-computer-history.c...a-website.html

Are you trying to completely eliminate being able to go on specific websites, or perhaps just limit the amount of time you spend on websites that may be interfering with your productivity?

http://www.onetipaday.com/2009/05/11...ite-you-visit/

Your other option is to use the Content Advisor thing, and to use some sort of self control or unlearn how to deactivate it.

You could also consider therapy or self help groups or treatment centres for addiction.